


Five Soul Mate Mark AUs That Never Happened to Leonard McCoy and One That Did

by TAFKAB



Category: Star Trek: Alternate Original Series (Movies), Star Trek: The Original Series, Star Trek: The Original Series (Movies)
Genre: Addiction, Alcoholism, Angst, Cutting (sort of), DID I SAY ANGST BECAUSE ALL THE ANGST OMMFG, Drug Use, F/M, Lots of euphemisms for sex and masturbation, M/M, Other disturbing material warned in end-of-chapter notes (chapter 6), Profanity, Really Lots of Angst, Self-Harm, Suicidal Ideation, Tattoos, Tumblr prompts assembled from far and wide, You're gonna have FEELS, dark themes, some more angst, soul marks, soul mate AUs
Language: English
Status: Completed
Published: 2016-09-22
Updated: 2016-09-24
Packaged: 2018-08-16 16:50:14
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 7
Words: 12,782
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8110066
Author URL: https://archiveofourown.org/users/TAFKAB/pseuds/TAFKAB
Summary: The title speaks for itself as a summary.  I chose not to use archive warnings because there is an event from one of the AUs that would be warned and I didn't want to spoil you for it right off the bat-- I have the warning at the end of the last chapter if you want to scroll down and see it before reading chapter 6.These prompts were borrowed from various accounts on Tumblr; they collected in my mind over time so I'm sorry, but I don't remember where they came from to give credit.  I think most of the tropes are fairly well-known anyway.Thanks to Adenil for support and suggestions!  :-)  Also thanks to ScarletJedi and McKirkish for emotional support when part 5 fell through because it was waiting for me to find the idea that's there now.





	1. Chapter 1

**Author's Note:**

  * For [Adenil](https://archiveofourown.org/users/Adenil/gifts).

**Summary for the Chapter:**

> Chapter 1: Soul mate mark AU where McCoy's soul mate tattoo is like a mood ring; it changes its color depending on what his unknown soulmate is feeling at the moment and he's not sure exactly what that color means. (AOS Universe)

Everybody thinks Leonard McCoy’s soul-mark is defective. It’s pretty apparent from day one; when it appears on his arm somewhere around age three, his parents notice that it doesn’t have the usual color range you’d expect in a soul-mark. Instead of running through all the hues of the rainbow, it starts out with two or three, and every year he lives, it shows more gray. By the time he’s nine, it doesn’t show any color at all except dark, uniform gray. 

That doesn’t bother him much until he’s in his late teens. By then he’s studying medicine, and he starts to wonder what the lack of color means. Soul marks reflect the emotion of the soul-mate, and this one shows next to no evidence of emotions at all.

Maybe his soul-mate is clinically depressed.

Maybe his soul-mate is on the autism spectrum.

Maybe something’s wrong with the mark. 

He studies the mark, and using spectrographic analysis on the chemical make-up of the cells detects minute variations of color, but he has no idea what they mean. They usually tend toward warm oranges and brownish-reds. Sometimes yellower, sometimes browner. On very rare occasions, he picks up flickers of green. Even more rare than that, he gets the faintest flickering hint of pale blue, almost white.

He has no idea what the colors represent. He just hopes his soul-mate is happy.

He kind of doubts it, though.

******

His mark never seems to respond in a way that reflects anyone feeling emotions in response to Leonard’s presence; it certainly doesn’t glow in bright, happy colors when he’s around Jocelyn. 

In hindsight, maybe he should’ve taken that as a sign. 

*****

Leonard is standing on the bridge of the Enterprise when his mark erupts. It starts as a pulse of sensation in his skin, as if a thousand tiny insects are crawling over the mark. 

Chekov is speaking, Spock is answering, Uhura is running after him and terse voices erupt everywhere, but Leonard can’t pay any attention; his arm is on fire. Not with pain-- with light. It’s bright, virulent green, so much so the glow starts to penetrate his sleeve. Squinting against the blinding glare, he snatches for a jacket and muffles his arm.

“Holy shit,” he mutters, clutching at the jacket as if he’s bleeding and holding it tightly enough will stanch the flow. Whoever his soul-mate is, the bastard must be having some kind of unprecedented epiphany-- murderous rage, paralyzing terror, he doesn’t know what the fuck, just some insupportably intense something that’s all-encompassing, all-devouring; it’s taking his soul-mate’s mind and making it scream. 

As soon as he gets his arm wrapped, it finally penetrates his brain: Vulcan is collapsing around a black hole; Spock went tearing off down there to fetch his parents and anyone else he can grab. 

Leonard stares at his arm in disbelief: finally, a possible correlation between something in his life and the color of his arm. Maybe his soul-mate is down there on Vulcan.

Dying.

He shakes it off with an effort. Jim and Sulu are free-falling and Pavel tears off like a mad bastard, yelling about handling the beam-up himself, claiming he can do it. Bones takes off after him. If somebody’s gonna have to scrape Jim off the transporter platform and try to put him back together, it’s gonna be him. 

*****

His arm flares again when Spock materializes-- and Amanda doesn’t.

Bones isn’t ready for it to happen again so soon, but he’s got the jacket already wrapped around his arm, and he thinks nobody notices. They’re too focused on Spock; they’re too devastated by the empty transporter pad where Amanda Grayson ought to be. He hears panicked voices yammering, and knows Vulcan is collapsing. And through the jacket bleeds green light so intense it’s turning white.

Bones turns on his heel-- there’s nothing a doctor can do for anyone here-- and hurries away. Holy fuck, not now. Not this. Not _him._ Jesus _Christ_ , not him!

*****  
He wraps his arm in layers. Supportive athletic bandage, dark opaque tape, a carbon steel cast for stubborn broken bones. It doesn’t look much bigger than his other arm, when he hides the evidence under his sleeve. He thinks no amount of light can make it through all that. And maybe the worst of this disastrous day is over.

His suspicions have taken gut-twisting, heart-stopping shape. All he needs is one more outburst, and he’ll be sure.

Jim gives it to him. He can feel the invisible bugs crawling like mad all over his skin as Jim provokes Spock, wild flares of emotion and color surging on Leonard’s arm in tandem with every word that falls from Kirk’s lips. Nobody can see it, but Bones can feel it just like his arm’s about to explode. 

Now he knows.

It isn’t a clinically depressed person or a neuro-atypical.

It’s a fucking _Vulcan._ No wonder he never got any indication the bastard has feelings.

He _doesn’t._

….Only, it looks like he _does,_ if you push him hard enough.

McCoy’s so stunned he can’t even manage to come to Jim’s aid, for all that Spock’s nerve-pinching him right there on the bridge. 

How can that horrible green-blooded, tight-lipped, self-satisfied asshole be his soul-mate? How can he have waited all these years to find out it’s _Spock?_ McCoy can only stand and stare. He regrets the moment he ever laid eyes on the man. He regrets ever thinking he might _like_ him.

And still… holy fuck. Spock’s entire home planet just imploded, killing billions. His mother’s dead, ripped from his very fingers just as he thought he’d saved her. How the hell is he even walking upright? McCoy can’t help but either admire that kind of pig-headed stubbornness… or maybe question its sanity. 

Spock banishes Jim as McCoy watches; he orders him shot onto a fucking ice cube and takes the center seat for himself.

McCoy squares his shoulders. To hell with how Spock feels. To hell with all the colors on his arm. Jim Kirk’s the most brilliant military mind to come down the pike since… Pike. 

They need Jim right now, damn it! The only man who ever beat the no-win situation. Not some half-baked computer with a ramrod up his ass who doesn’t have a clue when it’s time to break the rules.

Soul-mate or no, he’s damn well gonna give that hobgoblin a _piece of his mind._


	2. Chapter 2

**Notes for the Chapter:**

> Chapter 2: Soul mate AU where Bones' soul mate bears someone else's mark, not his. (AOS Universe)

Jim Kirk doesn’t notice when he meets his soul-mate. He’s so busy with the test and the hearing and facing off to his accuser and just generally spitting in everyone’s eye that he doesn’t even notice the counter on his wrist.

McCoy does. He’s been watching it for a while, even if Jim hasn’t. The damn thing’s been counting down toward zero faster and faster for a week now. Jim Kirk’s about to meet his soul-mate at last, and he doesn't even know.

The numbers stop on zero and start to flash just as some prissy Vulcan hobgoblin steps up to the podium and Jim starts trying to flay chunks out of his hide.

“Who was that pointy-eared bastard?” Kirk is just about breathing fire. 

McCoy rolls his eyes. “I don’t know.” He can’t resist the impulse to goad. “But I think I like him.”

There’ll be time enough for Jim to find out. Once your counter zeroes out, if you don’t manage to figure it out and hook up with whoever you’re meant for, the letters morph and change into the soul-mate's name, just to whack you over the head with your own stupidity. 

Later that night, McCoy notices his own counter. He can still remember the day it bottomed out-- and he's quite well aware of the person he met that day. He also remembers the day the damned thing reset itself instead of showing a name and just started counting again. What the _fuck._ He quit looking at it after that. The damned thing’s obviously broken. 

This latest development probably happened during the last couple of days. He thinks back to the trial-- half of Starfleet was there-- and the graduation ceremonies. Hell, _all_ of Starfleet was _there._ It must have stopped during one of those.

He makes sure to keep his sleeves pulled down as much as he can, and he doesn’t say a word to Jim.

“What the _fuck_!” Jim sputters when he finally notices his own counter’s finished. “I didn’t even see when it bottomed out!”

“I did,” McCoy mutters.

“When?”

He rolls his eyes.

“WHEN?!” Kirk yells.

“At the hearing. Look, you’re a big boy. Figure it out on your own. It’s none of my damn business.” 

He certainly isn’t going to be the one to tell Jim Kirk he believes the man’s soul mate is the very same uptight, hidebound, stuck-up, holier-than-thou programmer whose pet algorithm he’s just sabotaged to beat the Kobayashi Maru test, a fucking emotionless Vulcan, a _male_ for Christ’s sake. He’s never seen Jim get in a lather over a male.

As for his own soul-mate, well. There are damn good reasons why he’s never put much stock in all that bullshit. 

*****

Spock comes to McCoy after they’ve been on the Enterprise for a couple of months. He’s frowning, rubbing his arm. He doesn’t want to come right out and say what’s bothering him, which puts McCoy’s teeth on edge.

“Well, tell me or go away,” McCoy finally blusters, and Spock sighs, rolling up his sleeve.

It’s definitely a soul-mark; McCoy can tell that right away. He blinks at it. It’s still unresolved; it looks like it’s struggling to come out. Kind of like sun-faded ink. 

“I didn’t think Vulcans got those.”

“We do not.” He looks at McCoy with worry in his brown eyes. “But this has been growing darker for some 7.63 weeks now.”

“You’re half-human. This is probably related to that. All there is to do is wait and see what it says when it’s finished.” McCoy knows it’s cold comfort, but it’s all he has. “When the name comes up, then that person’s your destiny.”

“My destiny.” Spock’s tone is the equivalent of the expression you make when you step in shit with no shoes on. “My destiny is immaterial. I choose to be with Lieutenant Uhura.”

“Then maybe that’s whose name will pop up there.” In McCoy’s experience, that kind of wish fulfillment never happens. It’s exactly the kind of romantic bullshit the universe likes to take a dump on. 

“Perhaps it is.” Spock brightens slightly and goes away.

McCoy glances at his own wrist. It doesn’t look much different from Spock’s. He sighs, feeling very put-upon, and goes to take something for his impending headache.

*****

He keeps glancing at Spock’s wrist. No good reason, really. He keeps glancing at Jim’s, too. It’s easier to get a look at than Spock’s. Spock treats his mark like a shameful secret.

He can already tell Jim’s is going to be written in Vulcan. Jim fumes and swears and sweats at it, trying to force himself to be able to recognize what it says in the Latin alphabet, but he isn’t going to be able to. 

Bones takes a different tack; he wears a large flesh-colored pulse monitor pasted over the inside of his wrist as often as he can. Because reasons.

*****

Jim’s given up. His wrist says “S’chn T’gai Spock.” Every graphology resource in the universe agrees. He’s taken to wearing his sleeves halfway down to his fingertips, just like Spock has. He keeps his mouth shut.

McCoy makes sure he gets a look at Spock’s arm during his annual physical. Surprise, surprise! It says James T. Kirk, plain as day. Spock flushes, a sallow green hue suffusing his cheeks and burning at the tips of his ears. 

McCoy keeps his face very carefully neutral; he knows damn well how his own personal universe works, and he’s been expecting this. Spock’s gaze is stony as he silently challenges McCoy to comment, giving him an almost sullen glare. McCoy meets the glare and stares right back. He won’t back down this time. He doesn’t give a shit what the green-blooded, pointy-eared sonofabitch thinks; Spock ought to know he’s not going to spread the news or try to interfere. It’s simple medical confidentiality, if nothing else. The details are up to them, goddammit. None of this is either McCoy’s responsibility or his choice.

When Spock looks away he snarls a little to himself, but he finishes the physical with consummate professionalism. 

When Spock leaves sickbay he goes into his office and clears his schedule for the afternoon, working meticulously, writing postponement notifications one at a time. 

When he’s finished he locks the door and takes out the surgical scalpel he keeps in his desk: it’s a state-of-the-art laser cutter, capable of sterilizing and cauterizing its own incisions. He could take a man’s leg off with it, if he wanted, and never worry about him bleeding to death afterward.

McCoy makes a sterile field, folds back his sleeves, and sticks out his left arm. 

The Vulcan characters wait there, mocking him, exactly identical to the ones on Jim’s wrist.

So do the Latin characters, exactly identical to the ones on Spock’s.

They won’t be there for much longer.

The tender veins lie right there under the thin skin, rippling the elegant script, but the scalpel is so precise it works in layers, molecule by molecule. He doesn’t bother with anesthesia. It already hurts a lot worse in a place drugs can’t touch.

McCoy doesn’t cut anything bigger than a capillary as he takes the strip of skin off himself for good. It’s about three centimeters tall and five or six wide. He burns it in the incinerator. His fingerprints are red on the latch. Cold sweat pours down his neck and chest, staining his armpits.

He heals the wound, but he leaves an ugly, twisted keloid scar behind on purpose. It serves as a stern reminder that the best things in his life were always meant for somebody else. 

Both of them.


	3. Chapter 3

**Notes for the Chapter:**

> Chapter 3: Bones’ soulmate’s name is written over his heart in Vulcan, but he never even identified the alphabet, much less got it translated. He never takes his shirt off so no one can see it. (Either Universe)

Leonard McCoy sits at his Soulmate Sixteen party and stares at the cake and the punch and doesn’t say much to his friends, who are excited over everyone else’s marks-- especially the ones who got names that matched up with other people they already know. _Especially_ the ones who don’t like each other much.

All he got was squiggles. Random lines and squiggles in a straight line down his breastbone. Everyone else has a name, and he has gibberish.

This is almost as bad as Andrew Wilkins’ party. Andrew’s mark never came in; seems he won’t ever have a soulmate. He remembers the blank, stunned look in Andrew’s eyes. 

He figures his expression is nearly as bad. He sits there, fingers absently rubbing the cloth of his T-shirt over the new mark, which tingles at the touch. 

“That’s alien writing. Lenny’s gonna marry a tentacle monster.” He hears the girls giggle, and his heart shrivels up inside. 

His life just started and it’s already over.

*****

When he’s twenty-four, Leonard McCoy marries Jocelyn Evers out of desperation. Her soul-mate died young in a shuttle crash, and as far as he’s concerned, he doesn’t have one either.

It’s a disaster, except for Joanna.

Then Jocelyn takes her and goes.

He’s decides he’s pretty much done. Starfleet’s the only viable option he has left.

*****

Jim Kirk would’ve been a good soul mate, Leonard thinks. If he weren’t determined to have sex with everybody he meets, anyway. He’s at least fun to go drinking with, and Leonard couldn’t accidentally knock him up.

But he’s learned from the whole thing with Jocelyn, so he settles for being roommates with Jim. That way he gets some of the sweet and none of the bitter.

Turns out Jim doesn’t have a name on him. Instead, he has an infinity symbol. It makes Leonard laugh. _Of course he does._

“What’ve you got for yours?” Jim's curious, irrepressible.

“Just random scribbles.” Leonard clutches his T-shirt protectively to his chest and refuses to take it off unless he’s in the shower. He never takes his shirt off, and he never goes swimming. There are hundreds of alien species in Starfleet, and some things he’s just better off not knowing. 

*****

The first time he ever sees Vulcan calligraphy, he’s in Spock’s cabin. A book tumbles off a shelf, falling open. When he picks the book up Leonard goes white; his knees threaten to give way. Jim steadies him and helps him get the book closed without mangling it. Spock sets aside his lyrette and rushes to assist. 

“No! I’m fine, I don’t need help,” he babbles, and he flees before Spock can touch him, before Spock can sense his terror. 

The mark is written in _Vulcan._ A little research confirms his worst fears. It’s _Spock’s name._

He gets so fucking drunk the emergency medi-sensor in his quarters goes off, and Chapel rushes to the rescue. She has to pump his stomach and he needs a partial transfusion to drag him out of the alcohol-poisoning coma. 

He comes to lying on a bio bed with a sterile drape clutched in both hands so nobody can pull it off him, so nobody can see. His knuckles are white. Chapel cut his shirt away so she could treat him, but maybe he’s still safe; maybe she had the decency to let him keep it covered. He decides to play the incident off as an accident, bad judgment in response to news of a death from home, but in his heart of hearts, he wonders if part of him meant to die. 

He flees as soon as he can; he decides to get the thing tattooed over at his first opportunity. It’ll look dumb having a dark, heavy tattoo straight up his pasty white sternum, but he can’t deal with the alternative anymore. 

The tattoo idea is a good one. He's had it before, but he left it too late.

“I saw your mark.” Kirk tells him the first time they’re alone together. “Nurse Chapel and I were the first on the scene after the emergency sensor went off. She had to cut your shirt off you to resuscitate.” He pauses while Bones stares at the floor, his mouth alive with acid, like he’s bitten a copper conducting wire. 

“It looked like the writing in Spock’s book…. You never translated it, did you?”

Leonard shakes his head, desperate. “No,” he lies. “And I don’t want to.”

“Bones….”

“Leave it alone, Jim. It’s somebody else, okay? One of the Vulcans who died in the black hole. It has to be. The odds are billions to one.” 

Vulcans don’t even have soul-mate marks. They don’t believe in the concept of fate. 

He thinks of Spock and Uhura’s wedding plans, and something within him, some misbegotten hope he should’ve given up on years ago, withers and dies. It doesn’t go easily, twisting and tearing on its way out the door.

“Bones.” Kirk sets a hand on his shoulder. “I’m sorry, Bones. We covered it up before anyone else could see.”

Leonard excuses himself with proper gratitude and gets the hell out of Dodge.

*****

Leonard hides in his quarters with his head in his hands and remembers being bitterly disappointed at not knowing who his soul-mate would be. If that boy could see the grown man now….

He laughs, well aware of how hollow it sounds. How ridiculous it is to have the fucking hobgoblin’s name emblazoned across his chest! Fate has a really vicious sense of humor sometimes.

He gets a tattoo at Starbase Five. He chooses a caduceus with plenty of fancy background texturing. It swallows the mark whole. 

Turns out little Andrew Wilkins was the lucky one, after all.

**Notes for the Chapter:**

> For any naysayers, I chose to use a caduceus on purpose. Yes, I know about the Staff of Asclepius and its confusion with the caduceus; that's ancient history at this point in time. The caduceus is a commonly used replacement for the Staff of Asclepius, and I believe I've even seen it in Trek, though I might be mistaken. The caduceus is also more densely detailed and would more readily cover up Leonard's soul mark. If that makes me an ignorant American, I guess I'll just have to go buy a bunch of guns and vote for Trump to satisfy the rest of the stereotype. :-P
> 
> I. e., c'mon. This is a story that posits humans magically grow their soul-mates' names on their chests. Lighten up a little. 
> 
> If you still can't deal with the caduceus, you're free to imagine that Leonard went out and got a tattoo of a pink fluffy bunny instead.


	4. Chapter 4

**Summary for the Chapter:**

> Chapter 4: Spock can’t see color unless his soul mate’s soul mark touches his skin, and then his whole world changes. (TOS Universe)

The first time it happens, Spock is in sickbay. He has presented himself promptly for his quarterly physical as required by Starfleet regulations. 

Doctor McCoy is a consummate professional in some areas of medical endeavor. While he may fuss about his unfamiliarity with Vulcan anatomy and complain vociferously about its poor design, he puts on gloves to treat Spock. Thus the doctor considerately prevents him from experiencing telepathic discomfort from the necessary clinical touches that are bestowed during the examination. 

The incident occurs afterward, when McCoy has divested himself of the gloves and is helping Spock dismount from the bio-bed. His palm accidentally brushes Spock’s wrist for a fraction of an instant and everything goes strange.

Spock can’t explain it, but he sways, overwhelmed and dizzy, disoriented. It is as if for a moment he found himself transferred to an alternate universe, one where different spectral physics apply.

The odd effect immediately goes away as McCoy shifts. He puts him right back on the bio-bed and spends another half-hour scanning him, fretting. 

McCoy drives himself half-crazy, but he can’t find anything to account for the incident. Spock’s still right there; his eyes are still the same. He still lacks the necessary rods and cones in his visual receptors to interpret the spectral phenomenon humans call “color,” but his vision is quite satisfactory. He can distinguish over 10,000 shades of difference between black and white. He can observe magnetic fields and object density. He has a limited ability to perceive objects in tones of heat or cold based on the speed of molecular motion, which can be quite convenient when there is no visual light available. In fact, his vision is quite superior to the human norm. 

He catalogs the incident and files it as an interesting anomaly, and is prepared to retrieve his impressions should repetition necessitate a more serious investigation into the phenomenon. 

He notes, thereafter, that McCoy remains exceptionally careful not to touch him. Far more so than at first; there are no repetitions of the inadvertent contact. 

For two men who work as closely as they must, however, permanent suspension of accidental contact is a practical impossibility. They are working together in the laboratory approximately three months later when the ship is struck by a photon torpedo fired from a formerly cloaked Bird of Prey. The resultant concussion causes them both to fall against the bulkhead, and Leonard’s hand rests on Spock’s neck for approximately 4.8 seconds before they are able to retrieve their balance, enabling him to withdraw. 

The phenomenon is repeated, and Spock finds himself fascinated by the sheer strangeness of the world as it is revealed to him during those brief seconds. He did not know such… brightness could exist. Leonard’s shirt is vivid; it is compelling. Spock wants to touch it, to see if he can feel this strange new phenomenon in addition to seeing it. He wonders if Jim’s shirt is the same, and thinks it is not. Jim’s shirt is a different shade, farther from black. He is aware that his own shirt and McCoy’s are both the shade humans refer to as “blue.” Jim’s is “gold.” 

He touches his own shirt. It feels as it has always done. He would find that a disappointment, if he allowed himself.

He is curious to repeat the experience, and would be willing to allow McCoy to touch him in pursuit of the experiment, but he feels curiously reticent to ask, as McCoy is obviously reluctant to allow such contact. 

When he contrives to brush against McCoy’s fingers one day on the bridge, nothing happens. Spock considers this; he touched McCoy’s left hand on the bridge, but the incidents occurred when he was subject to contact from the right.

Further experimentation demonstrates that McCoy will let him fall rather than reach for him with his dominant right hand. 

*****

“What does the color blue look like?” Spock asks Jim-- not long after having explained his color blindness to the captain: a matter of rods and cones and hybrid physiology-- before presenting his query. “How would I know it if I saw it?”

“You’d know it because it’s the color of the shirt you’re wearing?” Kirk fumbles for a better answer, seeming a little uncomfortable. “It’s the color of the sky on Earth. The color of, hm, well. What else is blue around here? Some of the walls. Some of the floors. Some of the food cubes. There are lots of shades of blue, you know. Some are cooler, some are warmer. Some have more red in them. Some have more gray.”

Spock doesn’t know, and that is troublesome. How can a color have temperature?

“His eyes are blue,” Kirk points to McCoy. 

Spock raises a brow. “Fascinating.” He has noted the doctor’s eyes are quite pale compared to his own, but he was not aware they were significantly different from Jim’s, which have only slightly more intensity of black in the irises. The doctor’s eyes do not have the same amount of black intensity as his own shirt. He is confused by this. 

For the next week, Jim points out items and tells him what color they are. Spock is baffled. Sometimes three items have identical amounts of black in their shading, but the captain tells him one is blue, one is red, one is green. 

McCoy listens occasionally, but makes no contribution. 

*****

“Doctor, I wish to venture an experiment.” Spock’s curiosity has got the better of him; he is prepared to endure a certain amount of humiliation to test his hypothesis, and to gain a deeper understanding of what both the captain and his research have revealed to him.

“What’s that, Mr. Spock?” McCoy is lounging comfortably, gazing down into a microscope with his “blue” eyes. 

“I wish to duplicate a curious phenomenon. I have experienced it twice before under circumstances of physical contact with you.”

McCoy stiffens and lifts his head. He raises a brow; he makes no move to touch Spock. “Oh? And what phenomenon is that?”

“It is not something I am able to explain at this time,” Spock confesses. “However, I theorize that contact with your right hand produces a chemical reaction that enables me to see color.”

“That’s ridiculous.” McCoy keeps his right hand carefully on the opposite side of his body from Spock.

“I am not in the habit of making observations that are not grounded in fact.”

“If there’s a chemical reaction, it’ll happen with my left hand, too.” McCoy offers that hand. “I’m busy, Spock. Help yourself.” His heart rate is curiously elevated; Spock can hear his pulse pounding in his throat. 

“I have already ascertained that the left hand is not efficacious in producing the desired response.” 

McCoy shakes his head with exasperation. “I think you’re imagining things.” He reaches out with his right hand and puts his fingertips on the back of Spock’s hand.

Nothing happens. McCoy’s emotions are wary, guarded, unwelcoming. He’s made a distinct attempt to shield, and is doing a good job of it, for a human. 

“Interesting.” Spock raises a brow. “Perhaps you are right.” 

Spock withdraws to contemplate the failure of his experiment. Later he returns with the intention of venturing it anew with altered parameters, only to find Kirk has gone to McCoy’s office before him. McCoy is sitting slumped, his head buried in his hands. Kirk has one hand on McCoy’s shoulder. When he notices Spock, he frowns, his forehead creasing, and makes a quick gesture: shaking his head, negative, and flicking his fingers. It clearly means _go_.

Spock goes. 

*****

The door to Spock’s quarter chimes later that night; It’s McCoy. He looks a little red-eyed but essentially intact. 

“Come with me to the observation lounge.” McCoy swallows, his adam’s apple bobbing in his throat. 

Spock does not question; he accompanies McCoy. 

When they arrive, McCoy leads him up to the forward viewscreen-- a place he’s never seen the doctor go on his own, not voluntarily. They are in orbit around Gamma Regula VI; the planet is M-class, endowed with a plenitude of oceanographic, topographic, and meteorological phenomena. Many crewmen have gathered to observe. They make way for ranking officers, polite.

McCoy swallows again. He offers his right hand, palm up. 

Spock reaches, carefully extending his fingertips. McCoy remains steady.

When his fingers touch McCoy’s palm, the faintest butterfly-kiss of skin, Spock’s world flares to light.

Spock is captured, captivated. The swirling clouds are suddenly a myriad of shades he has never anticipated; the oceans likewise. Everywhere are visual gradations he has no name for. It’s stunning; it’s aesthetically overwhelming, yet pleasant beyond anything Spock has ever imagined. 

He stands for many minutes, enraptured, his eyes drinking in every millimeter he can absorb. When the sun slowly vanishes over the terminator, illuminating the clouds in a million more unexpected shades, he is stunned.

McCoy stands beside him, forgotten, until darkness falls. When Spock returns to himself, he realizes McCoy is trembling. Sweat covers his skin, staining his shirt. His face is turned away.

He withdraws his hand in haste before Spock can see the color of his eyes. Spock’s world returns to normal, fading to shades of gray.

Spock watches McCoy walk away with his spine straight, not speaking. He remembers the many hues of the vast blue oceans, lightening and darkening as they shaded over shallow sands into deep trenches. He wonders which of those shades might reflect in McCoy’s blue eyes. 

As he watches McCoy vanish, he grows to understand that he has taken something from the doctor in this transaction, something he cannot fathom. Perhaps the chemical reaction produces an energy drain; perhaps the doctor needs electrolytes or a nutritional supplement. If so, he is surely qualified to prescribe and obtain such things for himself. And yet….

This gift must receive just recompense. If it damages the doctor, it should not lightly be repeated. 

*****

Spock anticipates McCoy would like several significant equipment upgrades for his sickbay, and orders the items without bothering to await a requisition. It is only a token payment, but he is resolved to do more, as opportunities arise.

*****

Spock finds his world has grown flat and dull, uninteresting. He is frequently distracted, wondering what he is missing in each new experience, in each moment. He wonders if his efficacy as a scientist is diminished by his lack. He decides that if it is, it can be compensated for via artificial enhancement through technological instrumentation. 

That is quite logical, but somehow, it is not satisfactory.

*****

McCoy avoids him. He is aware of it; it is not merely an avoidance of touch any longer. McCoy prefers not to be in the same room with him. It is a problem.

Spock will not countenance avoidance of the issue for long; it is important to him. He seeks McCoy out.

“I apologize if I inadvertently harmed you in the observation lounge, doctor.” He watches McCoy carefully.

McCoy shrugs it off, scowling. “It was worth it so you could see things like they are for once.”

If he did not have more urgent information to pursue, Spock would take issue with that phrasing; he has always seen things as they are. He has merely not been privy to a certain segment of the visual spectrum, just as McCoy cannot perceive infrared, ultraviolet, or magnetic fields. 

There are always things that Spock cannot see. But now he has grown to… regret... some of them.

“Perhaps the chemical reaction can be duplicated and I could obtain the result independently. Further study might yield a solution.”

McCoy’s eyes flare with irritation. “Were you trying to bribe me with those new med-bay supplies, Spock? It doesn’t work that way.”

“Does it not?” Spock seizes on the implicit knowledge in McCoy’s statement. “Then how does it work, since you are evidently familiar with the phenomenon?”

McCoy grimaces, shoving his hands into his pockets. “It’s just one of those things.” 

Spock is unsatisfied, but McCoy will say no more.

*****

Spock’s initial attempts to research the phenomenon are unsuccessful. After a week of fruitless scientific endeavor, he sits back and reflects, and begins again, allowing more esoteric and less reliable information to fall under the umbrella of his inquiry.

He eliminates possibilities one by one until the only potential explanations he has left are, frankly, apocryphal.

He taps at his console, aware that in a human, such behavior would be termed “fretting.”

Sir Arthur Conan Doyle, a connection of his mother’s family, once wrote that “if you eliminate the impossible, whatever remains, however improbable, must be the truth.”

Spock returns to his console to investigate the apocrypha.

*****

Spock goes to Kirk with the results of his research. He presents his observations and conclusions.

“Am I to understand such phenomena are common between _t’hai’la?_ ”

Kirk sighs. “The definitive Latin words would be _sodales_ or _amici intimi_. As you have discovered: soul mates.” He gives Spock a sidelong look. “I’m not familiar with the term you’re using.”

“The word _t’hai’la_ denotes a dear friend, a lifelong companion, a brother… or a lover.” Spock admits the last meaning reluctantly.

 _“Rem acu tetigisti.”_ Kirk smiles, a little lopsided, still resorting to Latin. “You’ve hit the nail on the head, Mr. Spock. Thus the problem.”

“Then soul mates are supposed to become lovers.” Spock frowns. 

“They’re frequently well-suited to do so.” Kirk hedges, evasive. 

“No other person would experience a similar phenomenon when touching Lieutenant Commander McCoy?”

Kirk sighs, looking at Spock with obvious disappointment. “In two seconds plus the word ‘lover,’ Bones has gone from your friend to ‘Lieutenant Commander McCoy,’ Spock. Consider that if you’re looking for insight into what’s troubling him.”

“He seemed pained by our close contact. I do not understand.”

“Soul-mate marks are supposed to work both ways.” Kirk sighs again. “As far as I know, you don’t have a mark, Spock. You’re half Vulcan; until you taught me that Vulcan word just now, I didn’t even know if your people had the concept of a soul-mate. How you hurt him…? Think of it like a short circuit. You provoke an excessive emotional flow that isn’t reciprocal, a condition that damages the source.” He stops, looking as if he wishes he hadn’t spoken, then resumes, gruff. “I don’t know. I’m not a theoretical metaphysicist.”

“Nor am I.” Spock considered, frowning. “I would prefer to remain color blind than do harm to-- to Leonard.” The name tastes peculiar on his tongue. He realizes he has never spoken it before. 

Kirk smiles, though; he’s said something right. “Now you’re sounding like his friend, Spock.” 

Spock nods and resolves that he will avoid physical contact with Leonard whenever it is feasible. He will readily give up the universe of color to keep McCoy safe from harm.

But he cannot help feeling regret that he has never seen the precise shade of blue that would appear in the doctor’s clear, expressive eyes.

**Notes for the Chapter:**

> I've doubtless made a hash of the way vision actually works for the purposes of this story, but hey. You're reading a magical AU where soul marks work. The laws of physics don't necessarily apply. (TOS universe)


	5. Chapter 5

**Summary for the Chapter:**

> Chapter 5: Soul-mark AU where McCoy experiences his soul-mate’s orgasms (AOS Universe)

**Notes for the Chapter:**

> Check the tags for potential triggers; they changed a lot since chapter 4.

Leonard McCoy has the most aggravating, frustrating, tantalizing, yet ultimately worthless soul-mate mark of all.

He can feel his soul-mate’s sexual pleasure (and he’s pretty sure his soul-mate can feel his). 

It’s really damned embarrassing. Growing up, he rarely feels his soul-mate get up to anything, but he can’t help himself. He’s a highly sexed teen boy and to quote one infamous old comedy act, “When the monkey’s bad, you gotta spank it!” 

Sometimes after he gets going, his soulmate joins in-- and that’s when things get really hot and really frustrating both, because Leonard would love to have a partner. He’d just about die for it, but this has to be the hardest way anybody could try to identify his soul mate. How the hell do you ever find out who’s been beating it when? It’s not like you can walk up to another guy in polite conversation and say “So, when’s the last time you shook hands with Cyclops? Whip it out and let’s see if we’re soul mates.”

That’s a good way to get punched, Leonard knows, and he prudently keeps his mouth shut.

By the time he’s thirty, he’s given up on finding his soul mate. He’s got both a divorce and a lost custody battle under his belt, and he doesn’t have the time and energy to ride the baloney pony very much anymore, not even when he could find a partner. 

When he does beat off, his soul mate doesn’t join in anymore; it’s been years since that happened.

After he joins Starfleet, he’s grateful he’s not in the habit of sleeping around or even whacking off. It’s not smart to fuck where you work, and pretty soon he finds himself cooped up on a starship for five years running. Everybody he might like to have a go at is either his subordinate or his co-officer or worse: one of his commanding officers.

Leonard grimaces at the last thought and goes to the gym to work off some steam so he won’t get tempted to say or do something really, really stupid.

Curse his luck, that’s about the same time the guy (or girl, or bug eyed monster; whoever or whatever) starts getting up to shenanigans nearly every night after a lifetime of disinterest. It always starts within an hour after alpha shift gets off. 

….Maybe that was a bad choice of words. 

Within a week, Leonard starts to consider the idea that his soul-mate’s aboard the Enterprise. The alpha shift timing thing is a pretty big coincidence. 

At first, he decides he might as well join in the fun. If his soul-mate is aboard, maybe they could meet up, see if they hit it off. They’re supposed to, after all. A little companionable mutual masturbation might be just the ticket to pique whoever-it-is to start looking for him.

So McCoy starts helping out. He’s getting pretty interested after a night or two. Things start right on time, and he’s handling himself lazily, appreciatively… when he hears a thump from next door. From Commander Spock’s quarters.

The thumping repeats itself, taking up a distinct rhythm, and he cautiously edges toward the wall, putting a tentative ear up against the paint to magnify things a little. 

Ooops. That’s definitely Lieutenant Uhura making those high-pitched squeaking yelps; Spock’s evidently brought her back to his place for a little bit of bumping uglies. Weird that it’s happening when McCoy’s soul-mate just started up. Crazy coincidence.

He makes himself scarce rather considerately. 

*****

The next night, the coincidence isn’t that funny, and McCoy swears a little before he gets the fuck out. It isn’t safe to go home till after two. Christ. The things he never wanted to know about Vulcan stamina!

_The things he never wanted to know about Spock and Uhura._

McCoy grinds his teeth and forces himself to smile at everyone all day long. They eye him warily.

*****

The third night he can’t deny it anymore. Three nights in a row, his soul-mate started up at the exact time Spock and Uhura decided to make the beast with two backs.

Leonard stares helplessly at the wall, shaking his head and swearing quietly to himself. Once is chance. Twice is coincidence. Three times… is proof.

Not much question who his soul-mate is, not now. Uhura is quite a pretty girl, of course… but she and Leonard just don’t get along particularly well. They don’t actually fight, but they don’t have much interest in one another, either. 

Besides, Leonard mostly likes men. Jocelyn was an aberration; in hindsight, he admits he married her because he wanted a kid. 

No, it’s Spock. That’d explain his adolescent habits-- or lack thereof.

He’s certainly making up for lost time _now_.

Fucking fucking fuck.

Literally.

*****

Six months later it’s gone waaay past funny. Now it’s hell. McCoy is hollow-eyed and cranky; he hasn’t slept well since he came aboard. He doesn’t have anymore illusions about meeting and falling in love with his soul-mate; the man is quite firmly taken. Hell, if he spends any more time launching the meat missile, he’s gonna wear the damn thing off.

What’s worse is McCoy can’t even join in and get himself off and go to sleep that way. He tried once or twice but it pisses him off to know Spock-- _his_ fucking soul-mate, goddammit!-- is next door with a woman, paddling up Coochie Creek. He gets so mad he can’t keep it up long enough to finish. That just makes him madder; it makes him more miserable. If he didn’t watch himself, he’d crawl right into a bottle and never come up again.

Instead, he starts to take sleeping pills.

*****

It’s just a few, at first, and they help for a while. But then he needs more of them if he wants to sleep. Every little sound-- and if he’d admit it, the sensually incredible but emotionally agonizing sensation of feeling Spock getting off-- wakes him up every damn time. And then the two of them go at it again, and again, and sometimes more.

McCoy takes stronger pills. Eventually that means he can’t get up in the morning without some extra help; he’s just not alert. Coffee just won’t cut it anymore.

He can’t request a transfer to another room; that request would have to go straight to none other than Commander Spock, who’d want an explanation. McCoy can’t even sleep in his office; the beta shift has to use it. 

He starts taking uppers to get himself going. Maybe they’ll get bored with sex. Maybe they’ll break up. Maybe he’ll find the magical cocktail that lets him sleep through the hullabaloo in his head without leaving him a zombie in the morning. 

Maybe he’ll keep lying to himself, and keep taking more and more pills.

Nowadays by the time he comes home at night, he’s so jittery he can’t keep his hands steady.

He takes a handful of tranquilizers and chases them with a slug of bourbon; he knows this shit can’t go on forever, but he’s so miserable he can’t stop. Maybe he can tough it out till the end of the mission and then bail.

*****

He doesn’t make it that long, of course. The pills betray him eventually: after a particularly bad night, he has to take more stimulants than usual to get himself out of bed. His hands shake so badly during surgery that M’Benga has to take over.

Of course the records show he’s been chipping. He never had the hacking ability to hide something like that from Spock, so it all comes out as soon as the first officer starts looking. 

Well, everything comes out but the motive, the reason why it all started. McCoy hasn’t got much pride left, but he manages to hide _that._

*****

Jim is devastated, of course. He promises Bones he can come back when he’s clean; he arranges the most respectable and efficient detox facility the Federation has to offer. 

McCoy nods without agreeing and looks half an inch to the right of Jim’s head whenever he talks to him.

He doesn’t look at Spock at all.

*****

A year later he’s off the uppers and the downers and he has a little practice helping addicts in downtown Atlanta. It isn’t much. He lives in a rathole apartment; he doesn’t care. 

Spock and Uhura are married now. He got an invitation before he left the clinic. There was fancy gold lettering in Swahili, or Vulcan, or both, or something. 

McCoy burned it unopened. 

He can’t see Joanna anymore; Jocelyn’s lawyers got hold of his Starfleet records and the judge ruled a drug addict was too bad an influence on a little girl. He’s got nobody, and he’s got nothing.

His dick twitches, warming up, and he swears like a sailor, then takes a big slug of bourbon. They’re at it again, of course. They always are. He’s just glad he won’t be asked to deliver the babies.

Unfortunately, it takes a while to drink yourself to death. It takes doing, too, but McCoy thinks he can just about manage it.

**Notes for the Chapter:**

> Sorry. JEEZ I don't know where this hardcore angst is coming from!


	6. Chapter 6

**Summary for the Chapter:**

> Chapter 6: Soul-mate AU where you receive a letter in your youth containing the last words your soul-mate will ever say to you. 
> 
> There's a warning in the notes after this chapter if you're afraid you can't take the angst anymore and prefer to be spoiled.

Soul-mate marks are strange things. They don’t make sense to Leonard McCoy. What good does it do to get a mysterious letter bearing your soul mate’s last words? How’s it useful not to know your soul mate until at least one of you is passing and the other one will probably be left behind, alone? 

The last words aren’t always spoken to you, either; usually they have very little apparent significance or meaning. Very few people are self-possessed enough to think of saying “Hello, full name and identification number, I am your soul-mate and we meet on so-and-so stardate and I die on such-and-what stardate of the following causes” on their death beds. No, you always get something like pointless like “I’ll be right back” or “Where’s my stylus” or “I love you” (which is nice but not very helpful) or even “Oh, shit--” which isn’t either nice or helpful. 

Some people never even get a letter.

McCoy isn’t one of those. He gets his letter three years after his birth. His parents keep it safe and they give it to him to open when he turns twelve. He breaks the heavy wax seal and pulls out the creamy, thick cotton-rag paper inside. The writing is waiting; it only says one word.

“Remember.”

Well, hell, it could be a lot worse, right? After all, people aren’t really dead as long as you remember them.

He thinks about the word off and on as the years go by. Not very often. He has a busy life, after all. Jocelyn tells him to remember all kinds of things-- to turn off the oven, to take out the trash, to start the dishwasher, to pick up a liter of milk for the baby. 

She never dies afterward, though. After the divorce and the lost custody battle, that’s enough to make McCoy feel just a little bitter. 

*****

It’s possible to live nearly your entire life without ever finding out who your soul-mate was. Most people aren’t sure in spite of the letters. The letters don’t seem to have any realistic purpose. You love and you hate, you live and you die… you face every day as it comes; you hang a stuffed lizard in your office and laugh when people are baffled by its six legs. It’s life; it doesn’t have to make much sense. 

Leonard accepts the people in his life and doesn’t ask who’s what. He treasures them and cares for them as best he can.

He loved Jocelyn. He loves Joanna. He loves Jim Kirk and frets and pisses and moans over the kid’s recklessness. He loves Spock and they fight like cats and dogs over anything at all. He gets an automated scheduler that goes with his rank. It’s part of the Enterprise’s main computer system, and nobody but the computer ever reminds him to remember things anymore. 

“That computer’s my god-damned soul mate,” he tells Christine once, and they laugh because its voice sounds just like hers. 

*****

After Jim nearly dies on Vulcan, McCoy knows he won’t sleep. 

He spends a while reading, finishes up his paperwork, and putters around. He pauses next to the emergency door in the bulkhead his quarters share with Spock’s. It’s unlocked, just like usual. If Spock ever needs to talk, ever needs someone to help him work through a few things, he can come right on in. McCoy snorts, amused. _Yeah, that’s never gonna happen._

He strips down to his shorts. “Computer, illumination zero.” He lies down on his bunk, stubbornly awake in the velvet blackness of his cabin, listening to the quiet hum of the ventilation system and feeling the throbbing purr of Scotty’s precious engines through the walls and the floor. 

There’s a faint sound-- the manual latch of the bulkhead door, for the first time ever. A hesitation ensues; a pause; then the sound comes again.

McCoy sits up on one elbow, blinking toward it in the darkness. Faint red illumination appears and builds as the door swings open. It resolves into a dull glow that reveals a silhouette standing there. Spock, unmistakeable. He’s naked. The red light gleams on the surface oils of his skin; it catches in the dusting of hair on his body, outlining him in a halo of red and the faintest gold. McCoy stares at the light caught on the edges of Spock’s flesh, speechless. His cock stirs and fills. His heart thunders wildly.

“Doctor.” Spock’s voice is a faint husk of itself; it is unsteady. “I find that I am not well. I require a sedative.” 

_Jim didn’t die,_ McCoy understands suddenly. _The koon-ut-kalifee isn’t resolved. It was a delay, not a reprieve._

“That’s not what you need, Spock, and you damn well know it.” His voice is very calm, very kind. He gets up, moving carefully, afraid Spock will startle and bolt. He pushes his undershorts down and leaves them lying on the floor.

He goes to Spock, moving slowly.

Spock stands trembling in the doorway, heat from his warm room flowing around him, a sensual caress on McCoy’s own bare skin. 

McCoy reaches out tenderly. He can’t see the look in Spock’s eyes, but he can imagine his helplessness, his need, his fear. 

McCoy sets his hands on Spock’s fever-hot waist and tugs him gently forward. 

It’s all the encouragement that’s required. 

*****

They turn to one another, after that, whenever things go bad. Spock comes to McCoy, curls around him, and makes love with him. In the darkness of McCoy’s quarters, they lie tangled on the too-small bunk and press every possible inch of their skins together. It’s comfort, it’s trust, it’s home. McCoy doesn’t need Spock to call it any more than that. It’s enough.

The night after the ugly business with the parasites on Deneva, after Spock goes blind thanks to his hasty experiment, McCoy is afraid to go to him. He sits at his desk, brooding. Though Spock did get his sight back-- thank God--! that doesn’t let Leonard off the hook. It might have been gone forever, and then what would Spock have done? 

He can tease, in public; he can maintain the charade in front of Jim. He can snipe a little about Spock not appreciating his beauty, just to keep up appearances.

But in reality, he’s devastated with guilt.

McCoy doesn’t ever turn out the lights; he decides not to go to bed at all; he can’t stand lying down so close to where he knows Spock must be sleeping. He sits at his work table for hours, rubbing at his grainy eyes. It should have been him who went blind.

The inner door rattles-- and he curses, surging to his feet in dismay. This night of all nights, he meant to lock it. Really he did.

Spock steps in, silent. He’s still fully clad. He raises a brow at McCoy as he shuts the door behind him.

“Spock--”

Spock steps close and sets a finger over his lips; he begins to undress.

McCoy blinks, startled. “Computer, lights to zero.” They’ve always made love in darkness, as if they could hide the truth even from one another.

“Computer, lights one hundred percent,” Spock corrects him softly. When his clothes are gone, he raises McCoy to his feet and carefully, attentively undresses him.

As they slowly lie down and begin to move together under the bright, unforgiving artificial light, McCoy thinks he could easily, joyfully drown in Spock’s beautiful dark eyes.

*****

After that, Spock joins McCoy in his bed whenever he wants. It happens very often.

Sometimes they make love. Sometimes they talk, and usually they argue. Sometimes McCoy goes into Spock’s quarters instead.

Years pass, and no one ever guesses… except maybe Jim. There’s a fond light in his smile sometimes when he looks at them together, a knowing softness in his eyes. 

He keeps their secret for many years.

*****

Engineering is a fucking mess; dead bodies lie scattered all over. Others lie dying where they fell, victims of radiation poisoning too advanced for McCoy to be able to help. He can’t even spare the time to comfort the dying; he and Scotty are the only ones left, struggling to lock things down. They’ve got to get Kirk that power; if they don’t, nobody will survive.

McCoy’s heart sinks when he sees Spock stride in; he knows that set to his jaw, that determined line to his spine.

“Are you out of your Vulcan mind?” He stops Spock short of the port. “No human can tolerate the radiation in there!”

“But as you are so fond of observing, Doctor, I’m not human.” Spock remains resolute.

“You’re not going in there!” It’s his last word on the subject. Goddammit, he’ll knock Spock flat on his ass with an injection if he has to. He’s not going in.

“Perhaps you’re right.” McCoy nearly collapses with relief; in his distress, it never occurs to him that he hasn’t ever won this easily. “What is Mr. Scott’s condition?”

“Well, I don’t think that he--” McCoy feels Spock’s hand fall on his neck, and understands his mistake too late. Consciousness wavers, his body slumping, all his muscles gone to water. But Spock didn’t give him the whole dose; he’s still conscious, aware of the Vulcan’s hands gently supporting him, propping him up. He wants to scream, he wants to cry, he wants to lash out with his fists-- but he can’t even move.

“I’m sorry, doctor. I have no time to discuss this logically.” He feels Spock kneel by him, feels that familiar, beloved hand settle on his face for one last time. Spock’s love floods into him, fills him.

“Remember,” Spock whispers.

Then he’s gone.

**Notes for the Chapter:**

> Warning: Temporary (and canonical) character death


	7. Alternate Ending to Chapter 5

**Summary for the Chapter:**

> By popular demand!

**Notes for the Chapter:**

> For warnings, check the notes at the end of this chapter.
> 
> Note: In this AU, Nero failed to destroy Vulcan.

The holovid news channels go berserk one day while McCoy's at work. He's treating a homeless man who pretty damn near killed himself with methamphetamine when his receptionist comes in and gives him wild eyes. He wraps up fast and goes into her office, where she has the holonet up on her computer screen. 

A newscaster is yelping into his microphone; behind him San Francisco is burning. There's a swath of destruction through the city about 300 yards wide. A second starship crashed into the bay a few miles away, all hands killed on impact.

It was the _Enterprise._

McCoy's legs give way and he falls into a chair, staring at the footage with horror, with numb and terrible disbelief.

They're all dead. All of them, thanks to a rogue agent named John Harrison and a rogue admiral named Marcus. Untold thousands are dead, and thousands injured. All McCoy's friends and co-workers are gone.

Jim.

Spock. 

McCoy didn't think he could cry anymore, not after losing his right to see Joanna, but that news is enough to make him sob like a baby. 

He gets up and totters out before the newscast stops yammering; there's a liquor store nearby with his name on it. Tonight's the night, McCoy thinks. He doesn't want to wake up tomorrow.

The news is on in the liquor store, too. It's believed that a Starfleet operative, as yet unnamed, beamed aboard Marcus's crashed dreadnought, pursued John Harrison as he fled, and killed him. 

McCoy is too far gone to feel satisfaction at the news. He buys the strongest booze he can get his hands on, and the clerk raises a brow at him. It's not his usual poison; it's much worse. 

"Friends in 'Frisco?" The clerk is sympathetic.

McCoy unscrews the cap as his credit chip scans. He takes a swig, then another. "Not anymore."

He goes home and does his absolute goddamnedest to drink himself into a coma he won't wake up from.

*****

Hands haul him off the rug and propel him to the bath. Hands hold him as he vomits. Hands administer hyposprays, wash him, dress him, hold cool, soothing glasses of water and make him drink. 

After a while he sobers up enough to look up at their owner. He sees a ghost. 

He slumps back into those hands, figuring that if this is the afterlife, maybe it's heaven-- or no, in fact; maybe it's hell. Yeah, it's probably hell. 

Hands gently tuck him into bed. 

*****

He wakes up warm and dry and clean and only a little hungover. He curses, bitter, and gets up.

He remembers the hands and freezes, sitting absolutely still.

He smells coffee and hears noise in the kitchen. He can smell eggs frying. A voice calls his name, and McCoy staggers to his feet, incapable of refusing to answer it.

*****

Spock looks like someone went after him with a baseball bat. His face is bruised and battered, bloodied. He has a long cut down his arm, and McCoy purses his lips in disapproval; it's scabbed over without Spock ever even removing his uniform, much less cleaning it. 

"I have killed Khan, the man known as John Harrison." Spock speaks, his voice hollow. "The man responsible for the destruction of the Enterprise. ....You are the only one of my friends who is left alive."

"Nice to know I'm your absolute last resort," McCoy says bitterly. The coffee is black and very strong. He wraps himself around his mug and inhales the steam, waiting for it to cool. 

"You will not drink any more alcohol," Spock says, stating it as a blunt fact. "I have emptied all your bottles."

McCoy swears savagely, seeing confirmation in the gleaming pile of glass in the recycling bin. "You evil asshole. You motherfucking green-blooded sonofabitchinbastard. Who the hell gave you the right to come in here and do this shit to me?"

Spock ignores him, putting down a plate of eggs: half of an omelette with onion, green peppers, and tomato. "Eat this, doctor, or I will compel you." 

Neither of them enjoys breakfast. 

*****

A ship comes for Spock only three days later: a little Vulcan courier, courtesy of Ambassador Sarek. 

Spock doesn't have clearance to leave Earth, and there's quite a considerable kerfuffle about that, but in the end, Starfleet would've had to shoot the ship down to stop him and Spock refuses to stop for anything short of that. They let him go, blustering and yelling threats about diplomatic repercussions and irrevocable consequences and hearings and investigations and trials and court-martials.

Spock takes McCoy with him.

McCoy swears all the way through the involuntary beam-up, then swears as Spock puts him in a cabin of his own, then swears some more when he searches the entire ship and finds there isn't so much as a bottle of rubbing alcohol anywhere on board. 

De-tox symptoms start soon after: nausea, shaking, anxiety. They increase. McCoy curls into a corner and shivers and sweats. Then it gets worse; he's deep enough into serious alcoholism that he he gets violently agitated. He has heart palpitations and hallucinations. He's self-aware occasionally, enough to realize Spock is treating him for seizures. 

He figures the damned Vulcan is trying to make some kind of karmic reparations for letting the entire Enterprise go down and die. Maybe if he can play Jesus to McCoy, he thinks he can forgive himself. 

"Jim went to the engine room and attempted to help Mr. Scott effect repairs. He ordered me to go after Khan," Spock tells him once when he's mostly lucid. 

McCoy bares his teeth in a snarl and lies there, sweating like a pig. 

It takes him about two months to get past the last symptoms of AWS. By then he's settled in some kind of prison on Vulcan. Not that Spock would call it one. That's McCoy's word. It's a room in Spock's house or something. There aren't any windows. He has anything he could want except for his freedom and except for a drink. 

After his transfer into the room, McCoy never sees anybody but Spock.

Spock spends a lot of time with him, though they don't talk a lot. Apparently he's resigned his commission and McCoy is his new project. He wears civilian clothes in a strange mixture of Terran and Vulcan styles. 

"You can take your fucking guilt complex and your attempts to make up for it by fixing me and you can shove it all straight up your pointy-eared ass," McCoy spits at him one day. He wants a drink so badly he thinks he'd drink paint thinner mixed with piss. "If I want to drink myself to death it's none of your fucking business. You've got no right to stop me."

"On the contrary, doctor." Spock regards him, impassive. "My rights are irrelevant in this case, as you have no recourse to file a protest with the Federation consul."

"Fuck you."

"Do you feel that would be beneficial to your recovery?" Spock fixes him with those dark, inscrutable eyes. 

McCoy grinds his teeth until he thinks they'll crack. "Get. The FUCK. OUT." 

Spock goes, temporarily. The next day he's back as if nothing ever happened. He brings a box with him. McCoy won't look at it while he's there; he refuses to show an interest. 

He refuses to talk to Spock at all.

Spock leaves promptly at nine. By three McCoy's so desperately bored he opens the box. Inside he finds a collection of antique puzzles stored in plastic bins. The pasteboard pieces are well-worn, well-loved. 

He gets one out and sets out the pieces meticulously on his largest table. He gets the edge done before he collapses around dawn.

He sleeps most of the day, and is glad that he doesn't have to put up with Spock, who visits and makes food for him and leaves it stored conveniently for him to eat when he wakes. 

That becomes McCoy's new routine: avoiding Spock by sleeping all day and working on puzzles all night.

When the puzzles are all completed, new projects appear: a watercolor paint set, paper, an easel. Journals and diaries with old-fashioned fountain pens. As many books as a human could read in six lifetimes, all in English translations. 

Jim's clothes and belongings, neatly packed in boxes.

McCoy bellows himself hoarse over that gift, furious with rage and with weeping. He runs his hands over half-familiar leather jackets, jeans, shirts, boots. He puts on a pair of the jeans, belting up the waist till they'll stay on him. The boots are too large; he couldn't ever fill Jim Kirk's shoes. 

He waits for Spock wearing Jim's clothes. Spock winces.

"Is this what you wanted? You want me to be Jim for you?"

"No, doctor." Spock persists in calling him that. "I want you to be yourself."

McCoy snarls. He doesn't know who that is anymore. Maybe he never did. 

He packs up Jim's things and keeps them in storage. Sometimes he'll take them out to look at them, to catch a whiff of Jim's familiar scent. He picks one of Jim's jackets and makes it his own. Spock opens up his balcony-- albeit with a force-field around it in case he might think of jumping. Or in case one of the big prowling predators he sometimes sees decides to investigate the house; they look nasty.

The night desert air is cold. McCoy is glad of the jacket.

*****

Spock takes McCoy to a museum. He slouches around, feeling very unkempt compared to the sedate and prim Vulcans milling everywhere. He's clean, but he hasn't trimmed his hair or his beard in months. Spock stays very close by him. Sometimes Vulcans look at him oddly, but whenever they look over his shoulder at his protector, they withdraw with polite haste. 

He feels Spock's hand settle on his waist to guide him away from a recent painting-- a depiction of the San Francisco damage as night fell for the first time after the crash, all blood-red fire and smoke. He realizes he's been standing there a very long time.

"I'm not your fucking pet, Spock." He jerks away slightly, enough to break contact. He goes and stares at a red desert-scape for a while instead. The translated caption says something about composition and light. All McCoy sees is a blur. 

If his tears fall, none of the Vulcans are rude enough to let on. 

*****

McCoy recognizes the stages of grief as he starts working through them. Guilt's his favorite. Anger's number two. Would things have turned out differently if he'd stayed? He'll never know. He rages at his paintings, at the desert, at himself, at Spock. Sometimes he breaks things. They're replaced while he sleeps.

Spock remains quietly patient, keeping his own grief to himself. McCoy becomes aware that he's writing. Whatever it is, McCoy can't read it; the characters are Vulcan. 

He doesn't ask.

Sometimes he paints things he remembers: a still life of sickbay. The inside of Jim's quarters. The angle of Jim's shoulder and neck as he leans over his desk, the warm shades of his shirt and his hair. 

He decides to burn that one because he can't bear to look at it. He takes it off the easel, trying not to see.

"I would like to have that one," Spock says quietly. "May I?"

"Help yourself."

Spock takes it away. 

*****

McCoy is allowed the run of Spock's house. He discovers it by accident one day; he wonders how long the door to his room has been unlocked. There's no way of telling.

He takes advantage of his freedom often. He can go make and eat his own food. He can go outside (as much as anyone; the force fields are, indeed, meant to keep the le'matya out rather than to keep him in, but they're there). 

He discovers he can go into Spock's library. He does it late at night, when Spock isn't around.

There's a photograph of Spock and Uhura's wedding on Spock's desk, and one of Jim smiling his best big shit-eating grin. ...And one of himself, a candid, taken when he was absorbed in his work, oblivious. He can almost hear himself snapping terse orders at Chapel. He picks it up and scowls at it. Then he sets it back in its place on the desk, face-down. Fuck the fucking hobgoblin.

He goes back to his room.

*****

McCoy thinks about what Spock said to him that one time. He doesn't want to, but he can't help it. Was it an offer? Was it mockery? Was it just Spock's best way to get him to shut the fuck up? Probably the latter.

It's been eight months since John Harrison and Admiral Marcus tried and failed to start a war with the Klingons. During all that time, McCoy hasn't thought much of sex. He hasn't even wanted to.

When he thinks of Spock saying that, though....

He can't even touch himself. Spock would know.

*****

They go on like that for about six more months. McCoy meets Sarek and Amanda; they become frequent visitors. They actually live in part of this compound, not too far away. They're very kind to McCoy, especially Amanda.

Turns out Spock is writing a manifesto against military aggression in Starfleet, and laying out a proposal for reform institution-wide. Sarek smoothed over the trouble with Spock leaving Earth, and Spock was commended in absentia for stopping Marcus and Harrison. The entire crew of the Enterprise was commended posthumously. Ceremonies were held. Monuments erected. McCoy studies holographs of the slabs of marble, strategically positioned in San Francisco where Starfleet Headquarters is being rebuilt. 

The statue of Jim doesn't look anything like him.

He weeps uncontrollably sometimes and he isn't sure who it's for-- his friends, or himself. 

*****

Spock first touches McCoy fifteen months after the disaster. It's deliberate, McCoy knows. The Vulcan comes in to watch him paint, so McCoy stops and cleans his brushes, putting them away meticulously. He's lost the light anyway; soon it'll be dark outside. 

Spock lays his hand over McCoy's when he begins to fold his easel. Spock's skin is warm and dry.

McCoy swallows hard. 

"That damn plomeek again for dinner?" He keeps his voice level with an effort. 

Spock nods. 

"Don't take me wrong, Spock, but I could murder a nice big piece of beefsteak."

The next day Spock has a hibachi installed on his balcony and McCoy finds a prime cut of actual beef in the cooler. McCoy doesn't know how the hell Spock got his claws on something like this here, on Vulcan, but he cooks it medium rare and devours it all with bread, salt, and seared onions. 

If he has tears in his eyes as he chews and swallows, that's nobody's business but his own. 

*****

McCoy starts helping out at the local clinic. It's mostly minor injuries-- kids who fell and skinned themselves up trying to climb the big red rocks, the occasional domestic accident, a broken limb or two. He's surprised the Vulcan parents don't mind a seedy-looking human working on their children.

He shaves off his bushy whiskers and starts using beard-suppressor again. He finds a human barber who won't just give him a Vulcan bowl cut. 

His face is lean and unfamiliar in the mirror. It's more lined, more haggard than it was. He hardly recognizes it after so long.

Spock stops to stare at him for a long while when he discovers the change. His hands shake a little, maybe. 

Spock steps near and touches him again, a slow brush of one knuckle against McCoy's newly-bared jaw. Yes, his hands are shaking. McCoy is trembling too.

"The hell are you lookin' at?" He blusters. 

"Doctor Leonard Horatio McCoy," Spock responds. "For the first time in a long time, I think."

"It's just a fucking shave." McCoy draws a protective blanket of grouchiness over his discomfort and turns away. He doesn't know how to react to this softness in Spock, this refuge he's provided, his protection, his kindness. None of it. Why can't the pointy-eared jackass leave well enough alone?

McCoy also discovers he now has unrestricted comm access. In the process, he finds an email waiting, notifying him of his newly granted dual citizenship on Earth and Vulcan.

He doesn't bother call the Terran consul to say he was abducted, or to arrange any sort of rescue.

*****

At a party, a human colleague offers McCoy a shot of Jack. He looks down at the sparkling clean glass and the amber fluid inside it. He can smell the bitter-sharp savor.

His taste buds open up like he's just spent a week in the desert with no water; his tongue's practically hanging out. Spock's not anywhere around. Who's gonna know?

"No, thanks," he says, and gets himself a glass of tomato juice.

It's only one step, but it's a big one.

*****

His little practice expands; now he sees lots more adults. A number of humans live in the area; they need medical care, and they like the warmth and the security of knowing they've got a human physician. McCoy gets a bit of a reputation; he's becoming popular. He thinks it's because he doesn't dick around; he tells things like they are. 

By two years post-crash, McCoy's actually pretty content. He has his freedom. He thinks he could walk right off Vulcan and go anywhere he wanted. Spock wouldn't stop him.

He doesn't go anywhere.

He's processed a lot of grief, enough that his body wants to re-establish normal function. He still won't touch himself, though, not when he knows Spock might sense it, might guess it's him. Spock hasn't done anything since the crash, either. Thank God for that.

*****

One day the door chimes in his little clinic, and when McCoy looks up, an elderly Vulcan is standing there, smiling. He blinks, startled at first by the smile and then by the weathered, lined, familiar face behind it. 

"Hello, Doctor McCoy." 

"Ambassador Spock!" He's completely taken off-guard; he has no idea what to say. 

"It is good to see you. Our mutual friend suggested you might be ready to receive a visitor."

They spend a few evenings chatting-- arguing about the nature of causality, even-- while the other Spock makes himself scarce. It's bizarrely comfortable, surreal. McCoy enjoys the hell out of it, more than he's enjoyed anything in years. 

"Do not blame yourself for the unfortunate things that have happened in this timeline," Ambassador Spock advises him before he takes his leave. "Many actions in this universe have diverged from those in my own timeline, and few of them were of your choosing." He pauses, and his dimming eyes take on a moment of intensity, of uncanny sharpness. "My counterpart does not understand how deeply his choices affected you."

McCoy turns crimson. Does the ambassador know? He wonders whether this Spock would feel it too, if he--

Spock chuckles. "Stop fretting, Leonard."

He goes, and McCoy's Spock returns, and things go on as they were. McCoy's Spock publishes his anti-militarization manifesto, which causes a great stir. He's enough of a hero that the attention is mainly positive, even from the Federation.

*****

Spock receives an urgent communique from Starfleet. He sequesters himself to read and respond.

He's gone for a long time, and when he comes out, he doesn't speak. McCoy fixes dinner. He makes plomeek and serves it steaming hot. Spock eats without a word, preoccupied with his thoughts. McCoy eats too, even though he hates plomeek. It has a texture to it that puts him in mind of snot and cabbage. 

That night Spock touches himself. McCoy sits bolt upright in bed, startled awake by the half-forgotten sensation, staring into darkness. One of Vulcan's moons-- planetary companions, sure, whatever-- is rising over the horizon. It casts a dim blue light over the desert, and the pale illumination washes McCoy's bed in soft hues. He's been sleeping under a warm cotton quilt, a gift from Amanda. 

He stands up, shivering in the cold night air, and goes to find Spock.

Spock's room is dim, his balcony doors closed and curtained. He doesn't like the chilly night air.

McCoy stands in Spock's door, knowing Spock heard it glide open. Spock doesn't stop what he's doing, gazing up at his ceiling. He's naked atop his coverlet, and his hand moves slowly.

McCoy stares at him, and slowly his whirling, tormented mind disintegrates.

The first thing to come under his groping hand is a stone vase. He throws it; it shatters against Spock's wall, showering him with flowers and stale water. He throws a book next, and a padd, and a candlestick, warm wax spattering everywhere. He gropes again, but Spock is upright; Spock is coming for him; Spock has his wrists trapped in one hand; Spock is holding him against the door. Spock presses his fingers to McCoy's cheek, his temple, his chin.

Then Spock is in his mind, and he knows. He sees McCoy's misery, knows every minute of the long nights when McCoy grieved and suffered for want of him.

 _I am sorry_ , the voice fills him, shocked and contrite, coming from everywhere and nowhere. Behind it, he can feel the burgeoning heat of Spock's desire.

"Goddammit," Bones sobs. "I can't go through this ag--"

Spock's mouth covers his, galvanizing them both with sudden passion.

Leonard whimpers into it; his wrists are free and he drags Spock against him, ferocious, desperate. Spock draws him forward to the couch, and they fall onto it. For the first time, Leonard feels Spock's hand on him where it belongs. He lifts his chin and cries out in desperation and in his mind they are falling, falling, but Spock bears him up; Spock is solid and strong and for once, he is actually there.

_At last._

*****

"The Federation has offered to renew my commission as captain of the new Enterprise... to be dedicated to exploration, research, and scientific endeavor, to first contact and peaceful negotiation." Spock shows McCoy the letter he has received; McCoy stares at it in disbelief.

He sits perched naked in Spock's lap as he reads, their legs folded one pair over the other, his arm lazily hooked behind Spock's neck, Spock's looped around his waist.

Spock nuzzles against his throat, his tongue leaving a wet stripe that cools swiftly, making McCoy shiver, making his nipples tighten, involuntary.

"I will need a Chief Medical Officer," Spock murmurs against his skin. "I will accept only the best." His teeth are sharp but gentle as he bites kisses along the tendon in McCoy's throat.

McCoy thinks of Jim, of Chapel and Scotty, of Sulu and Chekov and all the others. His eyes fill with tears. He tucks his head against Spock's throat, breathing the warm spice of him.

"Dammit, Spock." He pauses to lick his way into Spock's mouth. "You know," he takes a second kiss, "I hate," he takes a third, "spaceflight." He silences Spock's impending retort at length.

"But I'll tag along, if you really want me." He swallows hard; Spock's eyes are sweet and warm. "Somebody's got to keep an eye on you, now Jim's gone."

**Notes for the Chapter:**

> Warning: Major and minor character deaths (and yet this is still the happy ending; go fig!)


End file.
